Apparatus for the conversion of hydrocarbons



July 20, 1937. M. P. YOUKER 2,087,533

APPARATUS FOR THE CONVERSION OF HYDROCARBONS Fil ed March 5, 1935 3 Sheets-Sheet 1 a/ mvilvrozz.

ATTORNEYS.

July 20, 1937. M. P. YAOUKE.R- I 2,087,533

APPARATUS FOR THE CONVERSION OF HYDROCARBONS. I

Filed March 5, l935 3 Sheets-Sheet 2 7M INVENTOR.

A TTORNEYS.

July 20; 1937. M. P. YOUKE R APPARATUS FOR THE CONVERSION OF HYDROCARBONS 3 Sheets-Sheet 3 Filed March 5, 1935 INVENTOR. I

ATTORNEYS.

Patented July 20, 1937 UNITED STATES APPARATUS FOR THE CONVERSION OF HYDROCARJBONS Malcolm P. Youker, Bartlesville, Okla, assignor to Phillips Petroleum Company, Bartlesville, Okla, a corporation of Delaware Application March 5,

6 Claims.

This invention relates to improvements in apparatus for use in hydrocarbon conversion processes and relates particularly to a valve which is especially adapted for controlling the flow and pressure of the products of a hydrocarbon conversion process.

In the thermal conversionof hydrocarbon fluids in processes of the type in which hydrocarbon fluids are heated to' high temperatures in a conversion tube while under high pressures followed by reduction of pressure on the products of conversion to effect separation thereof into liquids and vapors, there is a tendency toward the formation of solid or semi-solid carbonaceous deposits immediately in the vicinity of the point of reduction in pressure. This tendency is accentuated by any abrupt changes in direction or velocity of flow of the stream of hot products of conversion in the vicinity of the point of reduction of pressure and in apparatus using the ordinary type of pressure control valve, this results infrequent clogging up of the passages through the control valve and the connections in its immediate vicinity, causing frequent and costly shutdowns of the conversion process.

'So far as I am aware the only practical methods of preventing the formation of these undesirable deposits of carbonaceous materials are those which contemplate the introduction of relatively heavy oil in the vicinity of the point of expansion thereby cooling the products of conversion suificiently to stop the conversion reaction while at the same time maintaining a flow of sufiicient liquid material to keep the valve and its immediate connections flushed clean. These methods however are open to several serious objections, chief of which are the resulting'large increase in load on the subsequent fractionating apparatus due to vaporization of the added oil; the unavoidable mixing of at least part of the added oil with the liquid products of conversion, resulting in contamination thereof; and the necessity for additional equipment for stripping and recovering the added oil from'the liquid products of the process.

Because of these objections to the introduction of oil in the above described manner, valves have heretofore been designed which were intended to permit reduction in pressure on the products of conversion in such a manner as to prevent the deposit of carbonaceous matter in the pressure reducing valve or its immediate vicinity, but so far as I am aware none of these have proven very successful for the reason that the designers have apparently presumed that the carbonaceous 1935, Serial No. 9,466 (01. 251-29l deposits occur only on the low pressure side of,

the point of expansion, while as a matter of fact carbonaceous deposits also occur on the high pressure side of the point of expansion, though usually in the immediate vicinity thereof.

It is a principal object of this invention to provide an expansion valve so designed as to prevent the formation of carbonaceous deposits on the low pressure side of the valve discharge opening and at the same time provide for maintaining the high pressure side of the valve discharge opening substantially free of carbonaceous deposits throughout the period of operation without substantially altering the rate of flow through the discharge opening.

More specifically one form of my invention comprises a valve of the type in which the valve seat is formed in the discharge end of the conversion tube, which extends without bends or turns into a separating chamber for receiving the discharged products, a valve plug cooperating with the valve seat and operated by a hollow stem extending through the side of the separating chamber opposite the side through which the discharge end of the conversion tube enters the separating chamber, and at a point directly opposite, and in line with, the valve seat, and a car bon cleaning device located within the hollow valve stem and adapted to move through the valve plug into the discharge end of the conversion tube for scraping out the carbonaceous deposits which form in the discharge end of the conversion tube. The carbon scraper is adapted to be moved freely back and forth in the end of the conversion tube independently of the position of the valve plug and without altering the opening through the valve, thus permitting the removal of the undesirable carbonaceous deposits from the discharge end of the conversion tube without interrupting the operation of the conversion process. v

The invention will be readily understood from the following descriptiontaken in conjunction with the accompanying drawings in which' Figure 1 is a diagrammatic sectional view of an apparatusaccording to the invention.

Figure 2 is a sectional view of the reducing valve.

Figure 3 is a detailed sectional side view of a portion of the valve, showing-one modification of a valve plug assembly.

Figure 4 is] a sectional view taken along the line 4-4 of Figure 3.

Figure 5 is a sectional view taken along the line 5-5 of Figure 3.

Figure 6 is a detailed sectional side view of a portion of the valve showing a second modification of a valve plug assembly.

Figure '7 is a side View of the cleaning tool.

In the apparatus illustrated in Figure 1 hydrocarbon fluid, such as crude oil, gas oil, or fuel oil to be cracked, naphtha or gasoline to be reformed, normally gaseous hydrocarbons to be polymerized to normally liquid hydrocarbons or mixtures of these various materials to be converted to other materials is fed by means of pump P through a pipe I which'passes through furnace 2 wherein sufiicient heat is applied to the fluid passing through pipe I to effect the desired thermal conversion. From the furnace 2 the heated fluids pass through a connection 3 into a separating chamber 4 wherein the fluid discharges from'the connection 3 through a pressure reducing valve comprising a valve seat member 5 formed in the discharge end of connection 3 and a valve plug member 6 cooperating with valve seat member 5 to control the discharge of the heated fluid from the connection 3 and to regulate the pressure on the fluids undergoing conversion while passing through furnace 2. Upon discharge of the heated fluids into separato-r 4 and reduction in pressure the heated fluids will separate into vapor and liquid, the vapor passing upwards in separator 4 to be fractionated or further treated in any desired manner and the liquid collecting in the lower portion of separator 4 whence it is withdrawn through a connection, not shown, and disposed of in any desired manner.

Valve plug member Ii comprises an elongated cylindrical member which passes through the wall of separating chamber 4 at a point directly opposite valve seat member 5 and in the same horizontal plane in which valve seat member 5 and connection 3 lie. the portion of valve plug member 6 which is outside separating chamber 4 and cooperates with a gear 8 mounted on a shaft 9 through which motive power is supplied for moving valve plug member 6 with respect to valve seat member 5.

By thus positioning the valve with respect to the position of and the direction taken by connection 3 within the separating chamber 4, turns or changes in direction of flow or velocity of the heated fluids discharged through connection 3 are avoided and deposits of carbonaceous matter on the low pressure side of the valve prevented.

While the thus described arrangement of apparatus is generally successful in preventing formation of carbonaceous deposits on the low pressure side of the pressure reducing valve, never theless carbonaceous material will deposit on the high pressure side of the valve, particularly in the end portion of connection 3 which terminates in valve seat member 5. These deposits will usually 'occur within the last twelve inches or so of the connection 3 next to valve seat member 5. To permit uninterrupted operation of the apparatus, these deposits must be removed during the operation of the process and I have designed the pressure reducing valve proper so as to permit removal of these deposits without interrupting the operation of the conversion process. The valve proper will now be described in detail, reference being had to the various figures of the accompanying drawings Valve plug member 6 comprises an. elongated cylindrical member, the outside diameter of which is of such size as to make a close sliding fit with the inside walls of the valve seat member A gear I is mounted on 5 when valve plug member 6 is inserted therein. The end of valve plug member -6 which cooperates with seat member 5 is wedge-shaped and may be of the short-taper form shown in Figure 3 or of the long-taper form shown in Figure 6. The end of plug member 6 which co-operates with seat member 5 is'divided into two portions by a slot I0 which extends axially throughout a substantial portion of plug member 6, the forward edges of the slot I0 forming the leading edges ofthe wedge-shaped portion of plug member 6. Within the slot I0 is mounted a cleaning, tool II of such size and shape as to form a close sliding fit within the slot I0 and having a width substantially equal to the outside diameter of the plug member 6, thus forming a portion of plug 'memberIi. Cleaning tool II is mounted on an elongated cylindrical shaft I2 which extends entirely through plug member 6 to the outside of separating chamber 4 and beyond the end of plug member 6. Plug member 5 contains an axially extending boring to accommodate the shaft I2 in a closely fitting manner while permitting move ment of the shaft I2 through the boring. A

slot I3 formed in cleaning tool I I to accommo-- slot III.

A casting I5 fastened to a flange I6 which is supported on the wall of separating chamber 4 supports the plug member 6 and the operating apparatus therefor outside separating chamber 4. A casting I1 supports plug member 6 within separating chamber 4. Casting I5, flange I6 and casting I1 co -operate to hold plug member 6 in and packing '2I co-operate with plug member 6 to prevent leakage of liquid or vapors from separating chamber 4. A casting 22 is supported on the outside end of plug member 6 and in turn supports the end of cleaning tool shaft I2 which extends beyond the end of plug member 6. The end of shaft I2 is threaded and passed through bushing 23 having complementary threads and which is supported by the casting 22. A handle 24 for operating shaft I2 is suitably keyed to bushing 23 so that by turning handle 24 in one direction a forward movement without rotation is imparted to shaft I2 and by turning handle 24 in the opposite direction a backward movement without rotation is imparted to the shaft I2. The end of plug member 6 is threaded and passes through a threaded bushing 25 mounted in casting 22. A packing gland 26 prevents leakage of vapors or liquid from separating chamber 4 through plug member 6 along shaft I2. A portion of plug member 6 between separating chamber 4 and gear 1 is threaded externally and passes through a threaded bushing 21 supported by casting I5. Gear 1 is suitably keyed to plug member 6 so that turning gear 1 rotates plug member 6 and through the co-operation of Y the threads on plug member 6 and in bushing 21 imparts an advancing or receding movement to plug member 6. Connection 3 is suitably supported by the wall of separating chamber 4 by means of a structure comprising a flange28 fastened to the wall of separating chamber 4 and a sleeve member 29 which is in turn supported by flange 28. Connection 3 is supported within the chamber 4 by a support 30.

The valve will be operated in the following manner: Valve plug member 6 will be set at any desired position with respect to seat member by turning shaft 9 which will in turn operate gears 'l and 8 which will impart the desired forward or backward movement to plug member 6. The position of plug member 6 with respect to seat member 5 will be dependent upon the pressure which it is desired to hold upon the products of conversion passing through connection 3. When deposits of carbonaceous matter begin to build up in the discharge end of connection 3, cleaning tool II will be advanced into connection 3 by turning handle 24 which will turn bushing 23, which due to its threaded relationship with shaft l2 will impart the required forward movement to cleaning tool ll. When cleaning tool II has been advanced to the desired position inside connection 3, plug member 6 together with cleaning tool II will be rotated within connection 3 by manipulationv of shaft 9 and gears I and 8. To avoid changing the opening through the valve, plug member 6 and cleaning tool II will preferably be rotated approximately 180 in one direction followed by a rotation of 180 in the opposite direction. This rotative movement will cause the edges of the cleaning tool II to scrape off the carbonaceous matter which is deposited, on the inner walls of connection 3 and'the carbonaceous matter thus removed will be flushed out of connection 3 through the valve opening by the products of conversion flowing through connection 3. Cleaning tool H may then be withdrawn to its retracted position within plug member 6 until again needed.

Since theend of plug member 6 is wedgeshaped the edges of the wedge which are in very close proximity to the inner walls of connection 3 and seat member 5 will also serve as scrapers for the area contacted by as much of the length of the wedge as is inserted within seat member 5 and connection 3. It is therefore advantageous in some cases to use the long-taper form of wedge as illustrated in Figure 6, since it will be possible to make this wedge sufliciently long, so that even when the valve is partly open as in most cases, a substantial portion of the wedge will always be inserted in seat member 5 and connection 3: By rotating plug member 6 as above described the wedge end may serve as the sole scraping means. evident from the fact that carbonaceous deposits occur largely within the final 12 inches of connection 3 and seat member 5. If however the length of the wedge is insufiicient to reach all of the carbonaceous matter, the cleaning tool H can be utilized in the manner described to reach the more distant deposits of carbonaceous matter.

To facilitate the scraping action of the wedgeend of plug member 6 and cleaning tool II, the

edges of the wedge and the cleaning tool mayv be serrated.

The use of a wedge-shaped plug member has another important advantage over the usual cone shaped plug in that the valve openings formed by the co-operation of the wedge-shaped plug 6 and the circular seat member 5 always take the shape of segments of circles, as illustrated in Figure 4. This shape of opening will permit larger pieces of carbonaceous matter to pass through the valve than in the case of a coneshaped plug which forms a relatively narrow an- The feasabilityof this will be nular opening for a corresponding valve setting.

Cleaning tool I I may be of any desired length, though it is usually found that a length of 18 inches is suflicient to reach all of the deposits of carbonaceous matter which forms in connection 3 and seat member 5 under ordinary circumstances.

The diameter of shaft I2 is preferably equal to the thickness of cleaning tool ll, so that no widening of slot I0 is necessary to accommodate the shaft l2 when cleaning tool H is moved forward into seat member 5. Thus when cleaning tool II is in the fully retracted position there will be no openings of substantial size through the plug member 6 which might permit carbon to deposit within the plug member 6.

fluids, which have a tendency to deposit solid or semi-solid materials in the immediate vicinity of the point of discharge, without substantially affecting the rate of flow of fluids through the discharge opening.

Other advantages of my invention will be readily recognized by those skilled in the art.

I claim:-

1. A valve comprising a fluid discharge passageway, a valve seat formed in the discharge end of said passageway, a valve plug co-operat ing with said valve seat, a cleaning tool positioned within said valve plug and entirely retractable therewithin and adapted to be moved through said valve plug and into said passageway, means for operating said valve plug to change the cross sectional area of the opening between said valve plug and said valve seat and means for moving said cleaning tool through said valve plug and into said passageway without substantially altering the opening between said valve plug and said valveseat.

2. A valve comprising a fluid discharge passageway, a valve seat formed in the discharge end of said passageway, a valve plug co-operating with said valve seat, a cleaning tool completely retractable within said valve plug and projectable therefrom and adapted to move through said valve plug into and out of said passageway, means for changing the cross sectional area of the opening between said valve plug and said valve seat and means independent of said first mentioned means for -moving said cleaning tool through said valve plug into and out of said passageway without substantially alteringthe opening between said valve plug and said valve seat.

3. A valve-comprising a fluid discharge passageway free of bends or constrictions in the immediate vicinity of the discharge end thereof, a valve seat formed in the said discharge end of said passageway, a valve plug co-operating with said valve seat, a cleaning tool completely retractable within said valve plug and adapted to move through said valve plug into and out of said passageway and means formoving said cleaning tool into and out of said passageway without substantially changing the opening between said valve plug and said valve seat.

4. A valve, the same comprising a valve seat of a continuously uniform diameter, a valve plug of a diameter less than said valve seat and adapted to make a close sliding fit therewith, and a cleaning tool carried by said valve plug and projectable independently thereof into said valve seat to clean the same.

5. A valve, comprising a valve seat of a continuously uniform diameter, a valve plug of a smaller diameter than said seat and projectable thereinto and adapted to make a close sliding fit therewith, a channel in the end of said valve plug and a cleaning tool slidable therewithin, and means to project said tool into said seat to clean the same.

6. A valve, the same comprising a valve seat, a valve plug of a diameter less than said valve seat and adapted to make a close sliding fit therewith,

and a cleaning tool carried by said valve plug and independently projectable with respect thereto 5 to clean said valve seat.

MALCOLM P. YOUKER. 

